Molecular Characteristics Of Drug Resistance In Recessive Infected Bacteria Of Porcine Respiratory Tract In Henan Province

The respiratory diseases of Porcine is a serious threat to the development of aquaculture in China,which have become the main reason for the effectiveness of pig farms.,The incidence of more rapid detection for the virulence of the dominant sexual infection,but,it is difficult to detect for pigs with recessive respiratory infections.It is result that the pigs in long-term sub-health status,and it can cause more serious secondary infection and mixed infection.At present,There is little research on the species,distribution,pathogenicity and drug resistance of swine recessive respiratory pathogens in China and abroad.In this experiment,the pathogens were isolated from 114 pigs which come from 8 different cities in Henan Province.The identification of the isolated bacteria by means of 16 sr RNA PCR,BD Phoenix TM-100 automatic bacterial identification and identification.The resistance characteristics of the common drug and the molecular characteristics of the drug resistance gene were analyzed by micro-broth dilution method,PCR and sequencing.The aim of this study was to provide a reference for the clinical and effective prevention and control of recessive respiratory tract infection.In this study,245 strains of isolates were isolated from 114 pigs(with obvious lesions).175 strains(71.43%)of Gram-positive bacteria were isolated,including 70 strains of Staphylococcus,60 strains of Bacillus,12 strains of Streptococcus,Bacteria were 33 strains.70 strains(28.57%)of Gram-negative bacteria were isolated,Including 31 strains of Escherichia coli,19 strains of Klebsiella pneumoniae and 20 other negative bacteria.The type of isolated lung bacteria showed that the type of recessive infection of pig respiratory tract turn more,and appear in a mixed infection most.There were 20.41%(50/245)of the isolates,and 35 of them were Staphylococcus aureus,accounting for 70% of the total number of pathogens.It was presumed that Staphylococcus aureus was the main pathogen of respiratory infection in pigs,which had 53.41%(131/245)and it was the most pathogenic bacteria.Among which the Escherichia coli had the largest number of isolates,then it indicated that they had a certain effect on secondary and mixed infection of respiratory diseases.Other isolates were probiotics or nonpathogenic bacteria.In addition,133 strains of zoonotic diseases(conditional)pathogens in 245 strains of isolates may pose a serious threat to human health and animal husbandry,Therefore,Respiratory infection bacteria hidden separation had important public health implications.Resistance to phenotypic detection found that Escherichia coli,Klebsiellapneumoniae and Staphylococcus aureus multiple resistance significantly,three kinds of bacteria are amoxicillin,ampicillin highly resistant to amikacin,gentamicin highly sensitive,the sensitivity rate of 80% to 100%.Ciprofloxacin,enrofloxacin,cefepime more sensitive,the sensitivity rate of 77.14% to 91.43%.Bacillus in addition to the resistance to tiamycin significantly(resistance rate of 35.29%~63.64%),more sensitive to other common drugs.At the same time,we found that different types of bacteria on tetracycline drug resistance were significantly different,and the resistance to tetracycline,Among them,Escherichia coli,Klebsiella pneumoniae and Staphylococcus aureus were significantly more resistant to tetracycline(P <0.01),and Escherichia coli and Klebsiella pneumoniae resistance to tetracycline The rate was significantly higher than that of staphylococci(P <0.01).Detection of drug resistance genes found that although Escherichia coli,Klebsiella pneumoniae and Staphylococcus aureus phenotype characteristics tend to be consistent,but the carrier resistance genes are significantly different.Escherichia coli mainly carried TEM(73.29%),tet A(87.10%),tet M(54.84%)and flo R;Klebsiella pneumoniae mainly carried TEM(73.68%),SHV(89.47%),tet A(78.95%),tet O(42.11%)and flo R;Detection of Staphylococcus resistance genes revealed that the detection rates of tet A(32.86%),tet B(14.29%),tet C(10%),tet M(10%),fex A(47.14%),lsa A(35.71%)and lsa E(11.42%)were higher,The resistance of bacillus to Tiamulin was mainly mediated by vga B(40.74%)and lsa E(14.63%).In summary,the porcine recessive respiratory disease in Henan Province,the type of bacteria carrying bacteria complex and diverse,and 73.82%(181/245)of the isolates have certain pathogenicity,including Escherichia coli,Klebsiella pneumoniae,Staphylococcus aureus And Bacillus is the most common four kinds of isolates,and the first three kinds of bacteria on the common drug has a certain resistance,to carry multiple drug resistance genes;and Bacillus in addition to Tiamulin have significant resistance,the other drugs High sensitivity.